Detachable tread for tires.



PATENT OFFICE.

JUNIUS A. BOWDEN/OF 110$ A NGELES, CALIFORNIA.

DETACHABLE TREAT) FOR TIRES.

To all whom it may concern:

Be it known that I, JUNIUs A. Bowman, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and Statecof'California, have invented a new and useful Detachable Tread for Tires, of which the following is a specification.

This invention relates to means whereby the tread of a tire may be readily renewed at filo. 414,827, filed February 7, 1908, Serial No. 427,544, filed April 16, 1908, Serial No. 466,178, filed December 5, 1908, and Serial No. 468,397, filed December 19, 1'08, 1 have shown detachable treads consisting of devices in the form of studs which project from the surface of the casing and receive the wear and are detachable for purpose of renewal. In those applications I have shown various methods of detachably securing the studs in position and in the presentapplication I have shown a construction for securing the studs in position which I con sider to be an improvement over any of those which I have heretofore invented. In the present application I have also made an improvement in the wearing portion of the renewable tread whereby it is possible to provide a surface having a. much greater area for contacting with theroad'way and for receiving the wear than is afforded. by the single stud. Owing to the greater extent of wearing surface thus presented, the tread portion will wear for a longer period than the single studs and will thus not require so frequent renewal. In addition to the increased life of the tread portion, d have shown several forms wherein the traetive or anti-skidding qualities are equahif not;-

fipe'cification of Letters Patent. Application filed May 25, 1909. Serial No. 498,363. T

form shown in either Figs. 7 or 8.

Patented Jan. 21, 1913.

or extended contact portions as the means for securing such extended wearing portlons to the casing may be employed for securing single studs'in the casing whenever it is preferred to use the studs.

Further advantages of the present inventlon will be brought out in detail in the description.

Referring to the drawings: Figure 1 is a plan view of a portion of the tire showing one formof detachable tread wearing unit. Fig. 2 is a view similar to Fig. 1, showing another form of detachable tread unit. Fig. 3 shows another form of'detachable tread unit. Fig. 4 is a view similar to Fig. 1, showing another form of detachable tread unit. Fig. 5 is a view similar to Fig. 1, showing another form of detachable tread unit. Fig. 6 is a. View similar to Fig. 1, showing another form of detachable tread unit, the unit having an extended length and adapted to completely encircle the tire. Fig. 7 is an enlarged sectional View on line 4237-00 Fig. 4. Fig. 8 is a sectional view through the tread portion of the casing provided with a detachable stud. -Fig. 9 1s a perspective of the closing plug used in the Fig. 10 is a perspective of the detachable stud shown in Fig. 8. Fig. 11 is a perspective view in section of the receptacle used in Fig. 8. Fig. 12 is a perspectiveview of, the two members forming the expansible anchor.

Fig. 13' is a perspective of the expanding pin. Fig. 14 is a perspective view in longitudinal section of one form of cup. Fig. 15 is a plan view of the fabric adjacent the perforations. the anchor plate. Fig. 17 is a View similar to Fig. '7 showing a modification.

i Fig. 7 shows the means for detachably securing wearing units of the form shown in Fig. 4, as well as the other forms of de-' tachable tread units shown in Figs. 1, 2, 3, 5 and 6. 1 designates the casing of the tire which is. built up of any suitable material or combination of materials, for example, the outer strip 2 of rubber, the next strip of cotton 3, the next strip of thin rubber a, the next strip of-thick rubber 5, fol

lowed by a strip of cotton 6, the succeeding layers being repeated in reverse order Fig- 16 is a perspective of toward the inner wall of the casing. 7 designates a receptacle preferably of sheet metal pressed into shape, its bottom being formed with a depressed central portion 8 and the upper part of the receptacle comprising a flat radial flange 9 which unites with a cylindrical neclt 10 and the bottom of the lat ter unites with a flange 11 which is parallel with the flange 9, and the flange 11 unites with the side walls or main body portion of the receptacle. There is thus formed an external annular groove 12 and an internal annular groove 13. Permanently retained within the internal groove 13 is an anchor plate 14 shown in'detail in Fig. 16, which is formed out of sheet metal with a raised vertical flange 15 and the bottom having a central perforation 16. The anchor plate 14: is placed in position in the receptacle or cup 7 during the formation of the cup so that afterthe cup is fully formed the anchor plate is permanently retained within the groove 13; In one of the above mentioned applications of mine, Serial No. 468,397, which most closely approximates this form of fastening, the anchor plate is retained in the bottom portion of the cup by the stud which surmounts it, the anchor plate being prevented from rising by that part of the stud which intervenes between the flange 11 and the bottom of the cup. In the present case the stud is not depended upon for holding the anchor plate in the bottom part of the cup as the flange 15 of the anchor plate bears against the lower face of the flange 11 of the cup, thereby positively holding the anchor plate within the cup and the lower part thereof without dependence upon the stud. lVithin the cup is a lug 17, which corresponds to the lower part of the stud in the previous application referred to, the lug 17 projecting inwardly from the outer tread unit 18, the latter-resting against the outer surface of the casing and being secured within the cup by the lug 17 and correlated locking devices shown in Fig. 10. The lug 17 is formed with an external annular groove 19 and with a lower flange 20 which fits within the inner annular groove 13 of the cup. This flange 20 may be of less diameter than the lower flange of the stud in the previous application because in the present case the stud is not depended upon to hold the anchor plate 7, and thus the lug 17 may be more easily inserted inthe cup than when the flange 20 thereof is of greater diameter. This is important, as in the present case the detachable tread unit 18 is secured to the casing by the plurality of lugs 17 and as the lugs 17 are underneath the tread units 18 and as they-must accurately aline with the respective cups, itis morev ditlicult to insert them, which. ditliculty is minimized by reducingthe diameter of the flange 20.

The external contbur of the stud conit were cylindrical.

forms to the internal contour of the cup so that when the stud is in place in the cup it is snugly seated therein and the lower flange 20 is seated within the anchor plate 1 1 and fits the flange 15 of the anchor plate, while the neck 10 of the cup fits within the groove 19 of the lug 17. As the lug 17 is of rubber and compressible, it may be contracted to permit the flange 20 to pass through the contracted neck 10 of the cup. After the lug is in position in the cup itis detachably locked therein by means of two anchor members 21, each of which, as shown in Fig. 12, is segmental in form, and the top of each anchor member has a lip 22 and at the bottom hasfa foot 23. The lug has a conical recess 24 and the anchor members 21 are slipped through the recess 24 into position after the lug is in place so that each foot 23 is engaged under the anchorplate 141, while each upper lip 22 engages over a shoulder 24 formed in the stud. After the anchor members are in position an expansion pin 25 isinserted between the anchor members 21 and the latter are thus forced apart into intimate engagement with the" rubber plug and with the anchor plate. To fill the conical hole in the rubber plug above the anchor members, a filling plug 26 is inserted.

The conical shape of the filling plug 26 more securely retains it in position than if After the expansion pin 27 hasbeen inserted the lug is absolutely held within the cup and the tread unit 18 is thus securely locked to the tire and cannot possibly be removed therefrom without first removing the pins and anchor members 21. because the amount. of rubber which constitutes the flange 20 of the lug which is contained within the internal groove 18 of the cup is so great that it is impossible to compress it sufliciently to enable itto pass out through the annular space between the neck of the cup and the anchor members 21. The anchor members an not yield because they are positively prevented from doing so by the incompressible expansion pin 25. The engagement of the lips 22 of the anchor members with the shoulder 24 of the stud still further locks the stud in position. On the other hand, when it is desired to move the tread unit it is an easy matter to first remove the.filling 'ilugs 26 after which, by withdrawing the expansion pins 25, the anchor members 21 may be. slipped out and then the lugs will be allowed to contract sufiiciently lobe drawn out through the necks of the cups.

A further advantage of this construction is that the anchor members 21 are themselves mechanically prevented from accidental re- -moval because their feet 23 are positively held under the anchor plate 14 and the latter in turn is permanently retained within the lugs, one at each end for locking it in positending circuinferentiallyof the tire and in 'lugs 17. The side edges of each trea" unit- 'thus forniing a cont-inuous'tread wearing groove 13 of the cup and is 1nechanically held in the lower part thereof by the flan cs 15.

I e tread units may be of various forms. Fig. 1 shows each tread unit 18 as extending circumferentially of the tire and having two tion. Fig. 2 shows the tread unit. 18 exthe forin of a. strip which may encircle the tire, each strip being provided with the locking lugs spaced apart a suiiicientdistance to not appreciably weaken the casing and yet=e11fficient ly close together to securely hold thetread'units in place. Fig. 3 shows each tread unit 18 V-sh( ed and provided with three locking lugs, tl iere being a lock ing lug at each end of the unit and also one at the apex of the unit. The apexes of the units are preferably arranged in front so that the diverging arms of the tread unit tend to throw the dust and'mud laterally from the tire instead of scooping it in toward the center. Owing to the angular construction of the tread units this form is particularly eiiicacious in preventing skidding. Fig. 4 shows the tread'unit 18 of substantially square form held in place with five locking lugs. ihe respective'tread units 18 are spaced apart to form recesses 27' transversely of the tire which enablethe edges of the, tread units to take a odgrip on the roadway. Each of the trea units 18 is secured to the body of the tire b five prevent side slipping or skidding; Fig. shows the tread units 18 as arranged transversely of the? tire and ,set close together,

surface which completely encircles theiire. Fig. 6 shows a tread unit 18, which lS lfl the form of a wide single piece band which may encircle the tire anIdlogpi videdalong ockin each edge with a rowof g lugs suitably spaced apart for securingiit to the tire. The band 18 is further secured by: wires 18 in the edges thereof which bindit against the casing. Fig. 7, which is a section through 4 on line ca -00, shows the lug 17 to be integral with the'plate orunit 18. Fig. 8 shows the cup 7 constructed without the top flangeQ. In this form the outer rubber'layer 2 of thet-ire extends over the upper rifii'efcthe neck 10, the latter being below the surface of the tire. ThlS style cup permits of building up layers of cotton and rubber above the lower flanged portion of the cup, without cutting out or perforatin these layers any. more than the actual size of the upper neck portion of the cup, thus preserving the maximum strength of these layersgbringing thepeia. feet unbroke'ii circle (i -perforation in uniform close contact around the" neck of cup above the lower fiai iged bottom.

. Fig. 15 shows how the cotton, or other fabric 3, is formed with a selvage 27 around the 'edge of the orifice which strengthens the fabric at this point where it is most liable to tear. T

Fig. '17 shows a modification in which the" anchor plate 14 isheld in the upper part ofthe groove by a flange 15 which projects down instead of up as in the preceding. forms. The cup 7 may be secured by a screw 28 which passes through the depressed bottom portion 8 of the cup and through the underlying portion of the casing, and being screwed through awasher 29, the lower end of the screw 28 being headed to prevent the nut unscrewing. In this form the upper rim of thecup is doubledback on itself to form a rounded, edge, thereby giving a smooth surface which will not cut the rubher and also reinforcing the edge of the cup.

\Vhat I claim is:

1. In a tire, a cup in the tread portion thereof, said cup having an internal' shoulder, an anchor plate within said cup and retained below said shoulder, the anchor plate having a dished flange which holds the anchor plate below the shoulder, and a detachable tread portion interlocked with said anchor plate. e

2. In a tire, a cup in the tread portion thereof, said cup having an internal shoulder, an anchor plate within said cup and retained below said shoulder, the anchor plate having a dished flange which holds the anchor plate below the shoulder, and-a detachable tread port-ion interlocked with said anchor plate and also interlocked with said cup.

3; In a tire, a cup in the tread portion thereof-,, said, cup having an internal shoulder, 'an anchor plate retained below said shoulder and having a dished flange holding it below the shoulder, the anchor plate having'a perforated bottom, a renewable tread portionextending into said "cup, and anchor members engaging said renewable'tread portion and extending through the perforation in the anchor plate:

4. In atire, a cup in the treadportion thereof-,said cup having an internal groove, an anchor plate and unyielding means for positively holding it in the bottomof said groove; the anchor plate having a, perfo-- rated bottom, a renewable tread portion extending into thecup and having a perforation the walls of which havea shoulder, anchor members having lips engaging said shoulder, the anchor members extending.

and an expansion pin bet-ween the anchor members holdingithem apart. 5. In a the, a cup in the tread portion thereof, said cup having an internal groove, an anchor plate ii said groove, a renewable tread portion projecting into theeup and having a perforation, the outer-port10n of Y which is conical, means engaging in-said perforation and detachably connected to the anchor plate, and a conical plug fitting the conical recess in the renewable tread portion. I

6. As a new article of manufacture, a renewable tread portion for vehicle tires comprising a platehaving integral lugs adapted to seat inrecesses in a tire, the plate having a series of perforations which extend through the lugs and formed with internal shoulders, the wall of'ea'c-h perforation above adapted to receive a plug for filling in said.

cavity.

9. As a new article of manufacture, for the tread of tires, a metal cup having an internal shoulder, and a perforated anchor plate with a dished flange permanently secured in said cup, below said shoulder.

10, In a tire, a metal cup having an external annular hollow flanged bottom, the sides of the cup, above said flanged bottom being of smaller diameter and extending approximately straight to its top, said cup secured in the tr and, by means of alternate layers of canvas and rubber, said layers perforated of a size to register with the external diameter of said cup, the edges of said perforations being formed with a selvage above the flanged bottom, to make a snug fit and vulcanized thereto for firmly holding the cup in the tire, a detachable tread portion secured in the cup and projecting therefrom.

11. For vehicle tires, the combination of a metal cup, said cup secured in the tread portion tl'iercof, an elastic part dctachably locked in said cup, said part having an extension portion above the top of said cap formed with a conical shaped cavity, and a conical shapeo plug filling said cavity.

1.2. In a tire, a cup in the tread portion thereof, said cup having an internal shoulder, an anchor plate within said cup, the anchor plate havin an upwardly extending flange which engages the shoulder and holds the anchor plate below the shoulder, and a detachable tread portion interlocked with said anchor plate.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 20th day of May, 1909.

JUNIUS A. BOWDEN.

In presence of- 

